Machine Tools/Press

What is the technical name for a machine that presses, for instance, a piece of sheet metal into the basic form of a cheese grater? Just the holes and grating bumps. And then please clarify if it is called "machining" when the edges would be bent around a support rod on the sides.

Thank you kindly,

Maya

AnswerHi Maya,

That is typically known as a punch press. There are few variations, mostly in just the manner that they are powered and controlled. All piercing tools consist of a male punch and female die. The punch and die are aligned and when the press is cycled the punch enters the material and pushes it into the die creating a hole, shape or form. Picture a very large paper hole cutter, it's the same principle.

The second machine, if the manufacturer chooses to form the part that way is called a press brake. Again, it consists of a male punch and female die but bends material instead of cutting it. The tools are usually V shaped with the angle of the V being at whatever angle the manufacturer needs. The most common is a 90 degree V to for a square corner.

Cutting tools like cheese graters or knives are a sub-specialty in the stamping industry. Having never worked in that part of the industry I can only tell you how I would make tools for a cheese grater if asked. Assuming you are talking about a two sided tapered grater I would do it in two large tools, for the two different orifice sizes in the grater, coarse and fine.

They would be very similar, with the material being a long strip wrapped in a coil, like aluminum foil only very large. The first part of both tools would pierce and form the sharp edge of the grater holes, each tool with different diameter punches. I would then in second half of the tools cut off the part and bend the sides up while piercing the next one. This kind of tool that does more than one operation is called a multi-station tool.

The parts already being formed I would not need to form them in a brake. Next I would most likely employ a spot welder to assemble the two halves together. That is only how I would do it and again, having never worked in that part of the industry industry I could be way off.

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